There are hundreds of different red dot sights available. If you were to look for a specific mount for each of them, it would be almost impossible to mount any of such.
As the optic sights manufacturers are wise though, they started to copy footprints of already well estabilished manufacturers so that their devices can use the same mounting platforms.
In this article we will show which devices share the same mounting standard as the world renown Trijicon RMR.
Trijicon RMR mount compatibility
Trijicon RMR is one of the oldest sights on the market allowing mounting to pistol. And thanks to that it is also one of the most copied footprints. Or one of the most used footprint standards – whichever way you prefer to look at it.
List of red dots that use the same mount as Trijicon RMR
Here you can find all the brands and its models that share the same footprint as Trijicon RMR standard:
- Trijicon RMR
- Trijicon SRO
- Holosun 407C
- Holosun 507C
- Holosun 508T
- Swampfox Justice RMR 1×27
- Swampfox Liberty RMR 1×22
- Swampfox Kingslayer
Ade Advanced optics models
- ADE Advanced Optics RD3-019 Stingray
- ADE Advanced Optics RD3-020 Raptor
- ADE Advanced Optics RD3-023 Valkyrie
Vector Optics models
- Vector Optics Frenzy 1x22x26
- Riton X3 Tactix PRD
Trijicon RMR footprint standard in detail
You can find the footprint in full detail and measurements in this article: Trijicon RMR standard.
What is a red dot sight mounting surface?
The mounting surface, also reffered to as footprint, is the shape of the sight bottom. Usually its combination of sockets.
The mounting device, that is to accomodate the red dot sight, on the other hand uses a combination of pins. These pins are set so that they coallign with the sockets on the sight mounting surface.
The result of meeting these two surfaces will be that the bottom of the device will sit tight on the mount.
Of course pins and sockets is not the only combination that secure this. After first shot the sight would probably fly away anyway.
To secure the firm mounting there is also a set of screws (usually two screws). These attach the device to the mount through screw holes in both the red dot and the mounting device.
Luckily, mounting pattern standardization keeps things simple
If there were different mounting surfaces for each red dot sights, it would be very difficult to find mount that can accomodate such to the gun.
For that reason manufacturers started to copy mounting standards from each other. And based on the first red dot that came up with such mounting standard we recognize four most commonly used mounting standards:
- Trijicon RMR mounting standard
- Vortex Venom mounting standard*
- Shield RMS mounting standard
- C-More RTS mounting standard
*Vortex Venom actually was not the first red dot with this standard, often you will find this standard called “Docter”, but given Vortex Venom is nowadays much more common red dot, we will stick with Vortex Venom.
That is not to say that there are no more than 4 types of footprints. There is much more. But these four footprints cover vast majority of the devices available on the market.
Why is compatibility important?
Without the knowledge of compatible red dots you will have hard time looking for any mounting devices.
Or the other way, you will be only able to select from very few sights, not knowing that you can choose from much wider range of products. If you dont know that half of the Holosun red dot sights share the same footprint as Trijicon RMR, you may never consider buying such.
Also some sights use only part of the footprint. And with the knowledge of that, you can slightly adjust the mounting surface of a mount so that it will fit your red dot sight with otherwise unique footprint.
Trijicon RMR (“Ruggedized Miniature Reflex Sight”) was first introduced back in 2009 as an extremely durable red dot sight in compact size.
Its footprint consists of two sockets in the front, and two screw holes in the middle of the device.
The sockets are 22.5mm / 0.89 inches away from each other. The screw holes are 18.8mm / 0.74 inches away from each other.
Any mount with the same footprint standard will have two pins in the same distance so that when mounted, it will fit the sockets on the bottom.
Fixation to the mount is then secured by two screws that go through the screw holes through the sight to the mounting device.
Compatibility of footprints from other popular red dot sights
There are few more well-used mounting standards, each we covered in full detailed article: